Python logging Module Not Showing All Levels

about.md

• Inspired by this gist.
• Supporting documentation
• I made a new gist because I wanted to have a more complete example that compared what happens without using that solution versus using it.

code.py

# Python logger in AWS Lambda has a preset format. To change the format of the logging statement, 
# remove the logging handler & add a new handler with the required format

import logging
import sys

def setup_logging(name):
    logger = logging.getLogger(name)
    for h in logger.handlers:
      logger.removeHandler(h)
    
    h = logging.StreamHandler(sys.stdout)
    
    # use whatever format you want here
    FORMAT = '%(asctime)s %(message)s'
    h.setFormatter(logging.Formatter(FORMAT))
    logger.addHandler(h)
    logger.setLevel(logging.DEBUG)
    
    return logger

def lambda_handler(event, context):
    # Setup global logging config
    logging.basicConfig(level=logging.DEBUG)
    
    # Setup initial logger
    logger1 = logging.getLogger('logger1')
    
    # Setup separate logger
    logger2 = setup_logging('logger2')
    
    # For each logger, emit a message at each log level
    # For each log level, for each logger, emit a message
    for level in ['critical', 'error', 'warning', 'info', 'debug']:
        for l in [logger1, logger2]:
            getattr(l, level)(f'Testing level({l.name}): {level}')
        print()

output.log

START RequestId: 6bf3e28e-f5b8-433c-a70e-a0a98a417f19 Version: $LATEST
[CRITICAL]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger1): critical
2019-04-04 13:55:38,553 Testing level(logger2): critical
[CRITICAL]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger2): critical

[ERROR]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger1): error
2019-04-04 13:55:38,553 Testing level(logger2): error
[ERROR]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger2): error

[WARNING]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger1): warning
2019-04-04 13:55:38,553 Testing level(logger2): warning
[WARNING]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger2): warning

2019-04-04 13:55:38,553 Testing level(logger2): info
[INFO]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger2): info

2019-04-04 13:55:38,553 Testing level(logger2): debug
[DEBUG]	2019-04-04T13:55:38.553Z	6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Testing level(logger2): debug

END RequestId: 6bf3e28e-f5b8-433c-a70e-a0a98a417f19
REPORT RequestId: 6bf3e28e-f5b8-433c-a70e-a0a98a417f19	Duration: 0.98 ms	Billed Duration: 100 ms 	Memory Size: 128 MB	Max Memory Used: 41 MB